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The PPARs are ligand-activated transcription factors that belong to the nuclear hormone receptor superfamily. The three subtypes--termed PPAR-α, PPAR-δ and PPAR-γ--serve as lipid sensors in response to increased energy requirements [...], Huntington's disease (HD) is a progressive neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the huntingtin (HTT) gene, which encodes a polyglutamine tract in the HTT protein. We found that peroxisome proliferator- activated receptor delta (PPAR-δ) interacts with HTT and that mutant HTT represses PPAR-δ-mediated transactivation. Increased PPAR-δ transactivation ameliorated mitochondrial dysfunction and improved cell survival of neurons from mouse models of HD. Expression of dominant-negative PPAR-δ in the central nervous system of mice was sufficient to induce motor dysfunction, neurodegeneration, mitochondrial abnormalities and transcriptional alterations that recapitulated HD-like phenotypes. Expression of dominant-negative PPAR-δ specifically in the striatum of medium spiny neurons in mice yielded HD- like motor phenotypes, accompanied by striatal neuron loss. In mouse models of HD, pharmacologic activation of PPAR-δ using the agonist KD3010 improved motor function, reduced neurodegeneration and increased survival. PPAR-δ activation also reduced HTT-induced neurotoxicity in vitro and in medium spiny-like neurons generated from stem cells derived from individuals with HD, indicating that PPAR-δ activation may be beneficial in HD and related disorders.

[F.sub.1] hybrid male sterility is thought to result from interactions between loci on the X chromosome and dominant-acting loci on the autosomes. While X-linked loci that contribute to hybrid male sterility have been precisely localized in many animal taxa, their dominant autosomal interactors have been more difficult to localize precisely and/or have been shown to be of relatively smaller effect. Here, we identified and mapped at least four dominant autosomal factors contributing to hybrid male sterilily in the allopatric species pair Drosophila persimilis and D. pseudoobscura bogotana. Using these results, we tested predictions of reduced recombination models of speciation. Consistent with these models, three of the four QTL associated with hybrid male sterility occur in collinear (uninverted) regions of these genomes. Furthermore, these QTL do not contribute significantly to hybrid male sterility in crosses between the sympatric species D. persimilis and D. pseudoobscura pseudoobscura. The autosomal loci identified in this study provide the basis for introgression mapping and, ultimately, for molecular cloning of interacting genes that contribute to [F.sub.1] hybrid sterility.

This study examines mental health issues among women of different sexual orientations. An anonymous survey was administered at 33 health care sites across the United States; the sample (N = 1304) included lesbians (n = 524), bisexual (n = 143) and heterosexual women (n = 637). Not only did sexual orientation influence the probability of experiencing emotional stress, but also whether a bisexual woman or lesbian had disclosed her sexual orientation (was 'out') impacted the likelihood of having or having had mental health problems. Bisexual women and lesbians experienced more emotional stress as teenagers than did heterosexual women. Bisexual women were more than twice as likely to have had an eating disorder compared to lesbians. If a bisexual woman reported being out she was twice as likely to have had an eating disorder compared to a heterosexual woman. Lesbians who were not out and bisexual women who were out were 2-2.5 times more likely to experience suicidal ideation in the past 12 months. Lesbians and bisexual women who were not out were more likely to have had a suicide attempt compared to heterosexual women. Lesbians used psychotherapy for depression more commonly than did heterosexual or bisexual women. This is one of the few studies that compares lesbians, bisexual and heterosexual women. The implications of these findings are discussed. KEYWORDS. Sexual orientation, mental health, lesbian, bisexual women, sexual orientation disclosure, suicidality, eating disorders, methodology

Research reveals that the allosteric action of phosphoenolpyruvate increases with the increasing concentrations of MgATP influencing positively the binding of fructose-6-phosphate by phosphofructokinase of Escherichia coli. Data further show that alanine substitution for glutamate187 at the allosteric site activates fructose-6-phosphate binding.

Results demonstrate that MgADP binds to the active and allosteric sites of the E187A mutant of Escherichia coli. At high concentrations, it noncompetitively inhibits fructose-6-phosphate and low concentrations of MgADP competitively inhibits phosphoenolpyruvate without affecting fructose-6-phosphate binding. The allosteric effects are due to the combination of magnesium and nucleotide diphosphate.

The interaction between category structure and prior knowledge in category learning is examined in a series of three experiments. Topics include feature distribution, knowledge effects, and prototype theory.

Exercise intolerance may be caused by a mutation in the mitochondrial gene for cytochrome b. Cytochrome b is part of a group of enzymes called respiratory-chain complex III, which occurs in muscles. A study of five patients with exercise intolerance and evidence of complex III deficiency in their muscles revealed that each patient had a gene mutation in cytochrome b. Since their mothers did not have the mutation, it must have occurred spontaneously and was not inherited. Each patient had a different mutation although most involved a substitution of adenine for guanine.

Medin, Goldstone, and Markman (1995) recently described a series of parallel effects in similarity and choice. They suggested that similarity and choice are related in a nontrivial way such that choice may entail a similarity judgment to an explicit or constructed ideal. In this paper, the correspondences between similarity and choice were investigated with respect to a phenomenon in similarity known as the coincidence effect. In coincidence (pronounced 'coincidence'), two items that match on one dimension but have a large difference on another dimension receive a higher similarity rating than do two items that have only modest differences on both dimensions. We conducted five experiments in order to examine commonalities between similarity and choice processes with respect to coincidence. Four types of tasks were given: similarity ratings, desirability ratings, forced choice similarities (which of two items is most similar to a target), and forced choice preferences (which of two items one would prefer, given a target). We found a main effect for ratings as opposed to forced choices, with ratings showing greater coincidence effects than did choices. Similarity measures tended to produce more coincidence than did preference measures. The overall pattern of results suggests the presence of dimensional weighting processes sensitive to task characteristics and operating somewhat differently for similarity and decision making.

Proteins of the 14-3-3 family are well expressed in a variety of eukaryotes. While the 14-3-3 proteins are known to be involved in both cell cycle regulation and signal transduction, the specificity and nature of 14-3-3 binding is not known. However, it can be demonstrated that 14-3-3 proteins are phosphoserine-binding proteins. Moreover, research reveals that serine/threonine phosphorylation play important roles in the assembly of protein-protein complexes, suggesting that 14-3-3 interactions are critical to the activation of signal proteins.

A longitudinal study spanning nine years, in which four subjects learned and relearned 300 English-foreign language word pairs, was aimed at exploring the progression of the acquisition and retention of foreign language vocabulary as a function of the spacing between relearning sessions and the number of such sessions. The study was also aimed at linking the primary and interactive influences of these factors to the problems connected with the material. The retention advantage caused by additional sessions was unaffected by the advantage which the spacing provided.

The effects of a role-induction procedure on beginning counselor-trainees' perceptions of supervision were examined using a 10-minute audiotaped summary of Bernard's (1979) model of supervision. Nineteen trainees were administered the role-induction procedure at either the 2nd, 5th, or 9th week of the academic term. Two self-report scales assessed trainees' conceptualization of supervision as well as expectations and attitudes toward the supervisory process. Results indicated that trainees evaluated supervision more negatively over the time period before the role induction. Following role induction, trainees reported a clearer conceptualization of supervision and a greater willingness to reveal concerns to their supervisors.

A study examines the nature and dominance of epistasis between alleles derived from Drosophila persimilis which causes hybrid male sterility in the genetic background of its sister species Drosophila pseudoobscura, in order to assess its key role in causing hybrid incompatibilities. Results reveal that epistasis increases the dominance of individually recessive-acting QTL loci so that they play a role in hybrid male sterility.

A study to identify two isolating barriers that may reduce gene flow between Drosophila yakuba and its sister species Drosophila santomea who have overlapping ranges on the island of Sao Tome has been performed. The findings suggested that postmating, prezygotic barriers also contribute to the low frequency of hybrids.

Abstract The common law and civil law systems are generally considered as ostensibly different. They are nevertheless faced with similar challenges in terms of fact situations needing to be resolved. [...]

Research has been conducted on Drosophila santomea and D. yakuba. The genetics, nature and degree of sexual isolation between these species have been investigated via the use of different georgraphic strains, and the results are reported.

In 6 experiments, the authors examined the use of prior knowledge in category learning. Previous studies of the effects of knowledge on category learning have used categories in which knowledge was related to all of the category's features. However, people's knowledge of real-world categories often consists of many 'rote' features that are not related to their prior knowledge. Five experiments found that even minimal prior knowledge (1 knowledge-relevant feature and 5 rote features per exemplar) can facilitate category learning. Posttests revealed that although the knowledge aided learning, subjects also acquired the rote features that were not related to knowledge, contradicting predictions of an attentional explanation of the knowledge effect. The results of Experiment 6 suggested that subjects attempt to link even rote features to their knowledge.

Whose Torah? A Concise Guide to Progressive Judaism, by Rebecca T. Alpert. New York, NY: The New Press, 2008. 164 pp. $23.95. Rebecca Alpert is among the first women to [...]

ReThinking Synagogues: A New Vocabulary for Congregational Life, by Lawrence A. Hoffman. Woodstock, VT: Jewish Lights Publishing, 2006. 225 pp. $19.99. At the beginning of the 21st century, congregational life [...]

MAEVE BRENNAN Homesick at the New Yorker Angela Bourke New York: Counterpoint, 2004, $25.00 WRITER MAEVE BRENNAN (1917-1993) gives Angela Bourke an engaging focus for historical and sociological detailing of [...]

NUALA O'FAOLAIN Almost There: The Onward Journey of a Dublin Woman New York: Riverhead Books of Penguin Putnam, 2003 ALMOST THERE follows Nuala O'Faolain's remarkable 1996 memoir, Are You Somebody? [...]

Four experiments examined the extent to which prior knowledge influences the acquisition of category structure in unsupervised learning conditions. Prior knowledge is general knowledge about a broad domain that explains why an object has the features it does. Category structure refers to the statistical regularities of features within and across categories. Subjects viewed items and then divided them up into the categories that seemed most natural. Each item had one feature that was related to prior knowledge and five features that were not. The results showed that even this small amount of prior knowledge helped subjects to discover the category structure. In addition, prior knowledge enhanced the learning of many of the category's features, and not just the features that were directly relevant to the knowledge. The results suggest that prior knowledge may help to integrate the features of a category, thereby improving the acquisition of category structure.

LELAND BARDWELL A RESTLESS LIFE LIBERTIES PRESS, 2008, 25 €, 17.99 € I EAGERLY READ THROUGH Bardwell's memoir at one sitting; then promptly read it through again, both times finding [...]

MARGUERITE QUINTELLI-NEARY The Irish American Myth of the Frontier West Academica Press. Dublin, Bethesda, Palo Alto, 2008 I'VE JUST MADE ANOTHER of many transcontinental drives. It's a threshold experience every [...]

RODDY DOYLE Paula Spencer Viking, 2006, $24.95 ABANDON NORMAL reading pleasures, all ye who enter here: I have a hearing problem, a ruptured eardrum. A present from Charlo. It happened. [...]

JUDITH KITCHEN The House on Eccles Road Graywolf Press, 2002, $22.00 IF YOU LOVED The Hours, Michael Cunningham's prize-winning tribute to Virginia Woolf, you will want to know about Judith [...]

NUALA O'FAOLAIN My Dream of You Riverhead of Penguin Putnam, 2001, $14.00 NUALA O'FAOLAIN HAS WRITTEN A second book--a lovely and convincing novel--about being female and intellectually, aesthetically alive. While [...]